It goes without saying that an ultimate object of communication is to transmit or exchange one's will or information immediately to anyone any time from anywhere. In addition to the conventional fixed point-to-point communication, a mobile communication has been being developed gradually. The mobile communication is a communication between a moving body (including man) such as ship, automobile or aircraft and a general subscriber's station or an office and it is also a communication between moving bodies. Recently, portable telephone and cordless telephone which belong to the mobile communication have been developed actively.
In general, one uses a telephone set while holding the receiver to his ear and holding the transmitter in a position lose to his mouth, so even in the case of a portable telephone set it is necessary to ensure a sufficient distance between the receiver and the transmitter, thus resulting in that the portable telephone set itself has heretofore been somewhat long and large in size.
There has also been proposed a portable telephone set provided with a folding cover for protecting a switch portion of a portable telephone set. In this case, a microphone is provided on the cover side to ensure a sufficient distance between the speaker and the microphone.
Thus, in the conventional portable telephone set, the receiver and the transmitter both provided in the telephone set body are spaced apart by a distance approximately equal to the ear-mouth distance of the user, so there has been the problem that the reduction in size cannot be attained to a satisfactory extent. The manufacturing techniques for the constituent parts of portable telephone sets have advanced and it has become possible thereby to supply parts which are smaller in size and less expensive. From this standpoint it is relatively easy to attain the reduction in size of portable telephone sets. However, since there is a request from a human engineering stand that a distance approximately equal to the ear-mouth distance should be ensured between the receiver and the transmitter, this has been an obstacle to the reduction of size.
In the case of a portable telephone set having a folding cover which has been proposed heretofore, since a microphone is provided on the cover side, there has been the problem that the microphone cord is apt to be broken as a result of repeated opening and closing of the cover.
Accordingly, it is an object of the present invention to overcome the above-mentioned problems of the prior art and provide a portable telephone set capable of ensuring a sufficient distance between the receiver and the transmitter during use of the telephone set even if the size of the telephone set body is reduced to a sufficient extent.
It is another object of the present invention to provide a portable telephone set capable of protecting a switch portion while not in use and capable of improving the S/N characteristic in the transmitter.